Method of spooling or reeling artificial silk



May 15, 1934.

J. W. LUBBERHUIZEN ET AL METHOD OF SPOOLING 0R REELING ARTIFICIAL SILKFiled Nov. 10, 1932 I nWi Hem Lubberhuisen Hans /-\\wln chvenk .7):venfo rs new R TDKN CY Fatented May 15, 1934 PATENT OFFICE METHOD OFSPOOLING OR REELING ARTIFICIAL SILK Jan Willem Lubberhuizen and HansAlwin Schrenk, Arnhem, Netherlands, assignors, by mesne assignments, toAmerican Enka Corporation, Wilmington, Del., a corporation of DelawareApplication November 10, 1932, Serial No. 641,986 In Germany November14, 1931 3 Claims.

Our invention relates generally to the art of manufacturing artificialsilk and is directed more specifically to a method of spooling orreeling artificial silk in a manner to greatly reduce the windingtension which is a concomitant of present methods.

It is well known that the tension conditions through which a freshlyspun thread passes during the successive stages of coagulation anddecomposition may greatly affect the physical properties of the thread,such as its tensile strength and elasticity in dry and wet condition,its afiinity for colors, lustre and the like. It is also well known thattension acting on the thread at certain places during the stretchspinning process will materially increase the moisture resistance,dependent upon the coagulation and decomposition condition of the threadat such places.

The desired tensile strength of the thread is achieved by a number ofthe stretch spinning methods but in doing so the tension with which thesilk is wound on the spools becomes too great and in consequence thepermeability to washing and bleaching fluids is too slight. On drying on'i the spool the thread tends to shrink, as a result of which thetension in the inner layers of the fully wound spool still furtherincreases, while the outer layers of the silk are capable of yielding tothis shrinkage tendency during drying so that marked differences in thephysical properties of the threads of the outer and inner layers of thespool make themselves manifest.

Moreover, in consequence of this great tension the thread forms a veryhard layer on the spool and is stretched beyond the permissible maximum,the layers of thread being so tightly drawn into one another thatsubsequent unreeling, during spooling and like operations, isimpossible. Breakage of capillary and even of entire threads is notinfrequent so that the quality of the prodnot is materiallydeteriorated. The higher the original winding tension, the longer isthat part of the thread which does not yield good silk.

It is therefore an essential of satisfactory operation, particularly inthe case of artificial silk which must be stretched during itsproduction, to reduce the winding tension on to the spinning spoolproper. According to the method of our invention we accomplish thisresult, viz, the reduction of winding tension, by placing in advance ofthe winding spool a friction roll which acts with a gliding friction onthe thread and is driven in the direction of the thread take-off,whereby a release of thread tension is effected before the winding takesplace. The term fric- Fig. 1 illustrates, diagrammatically, portion of aan apparatus for practising the method of the invention.

Fig. 2 shows, on a larger scale, the friction rollers in plan View.

Fig. 3 is a side elevation of one friction roll shown in Fig. 2.

The rotating friction roll 1 which may have a peripheral speed of 100meters, draws the thread with gliding friction from the nozzle 2 out ofthe spinning bath 3 and preferably over braking elements 4 and 5 such asfriction rolls, guide rods or the like. The thread passes'from the roll1 to the winding spool proper 6, which may have a peripheral speed ofmeters. in this manner, the friction roll 1 relieves the thread of apart of the very great tension which is present in advance of the roll1, so that the Winding tension proper in the rear of the roll 1 and inadvance of the Winding spool 6 is relatively slight.

The friction rollers may consist of various materials, such as glass,porcelain or ebonite. As an alternative the surface of the rollers maybe coated with the said material. The coefficient of friction of therollers may be changed by the surface being unpolishe'd, particularly incase the surface consists of glass or porcelain, or by roughening etc.

The modus operandi of the braking rods or friction rollers will behereinafter explained with the aid of Fig. 2. The braking rods 5 mayconsist of glass or porcelain. The braking effect thereof can bemodified in the well-known manner by a change of the angle at which thethread engages the rods.

As Fig. 3 shows, the friction rollers are double rollers, in one of thegrooves 7 runs the thread 8 just spun, while in the other groove 9 restsa string 10 which is fastened at a fixed point 11 and kept stretched byan adjustable braking weight 12. Not only by a modification of thebraking weight but also by a displacement of the friction rollers inrespect to each other, viz, a modification of the wrapping angle, thebraking effect acting on the thread can be varied.

In further explanation of our invention, reference may be made to thetension conditions prevailing in cable and belt drives, which find theiranalogy in the present case.

By operating In Fig. 1

S1 indicates the tension of the thread in front of the friction roll 1;

S2 indicates the tension of the thread in the rear of the friction roll1;

e is the basis of the natural logarithmic table;

1 is the coefficient of friction between the thread and the frictionroll.

d is the looping angle, measured as a circular are having the radius 1cm.

, The tension conditions are then represented by the formula Evenwithout modification of the special friction j, i. e. without modifyingsay the nature of the thread or of the surface of the friction roll, thetotal friction may be easily changed by merely properly selecting thelooping angle d, so that it is possible to relatively adjust the twothread tensions S1 and S2 to every desired relationship; in other wordsS1 may be reduced any desired extent in relation to the tension S2.

We claim:-

1. The process of producing artificial silk which comprises extruding afilament and passing the same through a coagulating bath, conducting thefilament continuously as it is passed from the bath to a collectingdevice for forming a package, and causing the filament as it is passedto the collecting device to be propelled by a godet with which it has adesired friction contact, and effecting a drag on the filament inadvance of the godet to thereby cause sufiicient slippage of thefilament with respect to the godet to compensate for the tensionvariations occurring throughout the path of travel of the filament fromthe point of application of the drag to the collecting device.

2. The process of producing artificial silk which comprises extruding afilament and passing the same through a coagulating bath, conducting thefilament continuously as it is passed from the bath to a collectingdevice for forming a package, and causing the filament as it is passedto the collecting device to be propelled by a godet with which it has adesired friction contact, effecting a drag on the filament in advance ofthe godet to thereby cause sufficient slippage of the filament withrespect to the godet to compensate for the tension variations occurringthroughout the path of travel of the filament from the point ofapplication of .the drag to the collecting device, and effecting astretching of the filament, the stretching being effected principally atthe point of application of the drag.

3. The process of producing artificial silk which comprises extruding afilament and pass ing the same through a coagulating bath, conductingthe filament continuously as it is passed from the bath to a collectingdevice for forming a package, and causing the filament as it is passedto the collecting device to be propelled by a godet with which it has adesired friction contact, effecting a drag on the filament in advance ofthe godet, and effecting a reduced tension on the portion of thefilament between the godet and the collecting device with respect to thetension on the portion of the filament be' tween the godet and the pointof application of the drag, whereby to compensate for the tensionvariations occurring throughout the path of travel of the filament fromthe point of application of the drag to the collecting device. 7

JAN WILLEM LUBBERHUIZEN. HANS ALWIN SCHRENK.

